Former Secretary of State Colin Powell on Thursday endorsed President Barack Obama for reelection, arguing the president has improved the poor economy he inherited and sharply criticizing Mitt Romney’s foreign policy positions as a “moving target.”

“I voted for him in 2008, and I plan to stick with him in 2012,” Powell said of Obama on CBS’s “This Morning.” “I’ll be voting for he and for Vice President Joe Biden next month.”

One of the most coveted endorsements remaining in the 2012 presidential race, Powell said Obama walked into a horrendous economic situation and has begun to turn it around.

“I think, generally, we’ve come out of the dive and we’re starting to gain altitude,” said Powell, who served as George W. Bush’s secretary of state. “It doesn’t mean all our problems are solved.”

While Powell, a Republican, said that he had the “utmost respect” for Romney, he charged that the former Massachusetts governor hasn’t outlined how he would pay for increased defense spending or for his proposed across-the-board tax cut.

Powell had even harsher words for Romney’s foreign policy, questioning his changing stances on withdrawing from Iraq and Afghanistan.

“The governor who was speaking on Monday night at the debate was saying things that were quite different from what he said earlier,” Powell said.

“I’m not quite sure which Governor Romney we would be getting with respect to foreign policy,” he added. “I don’t sense he’s thought through these issues as thoroughly as he should have. He gets advice from his campaign staff that he then has to modify as he goes along.”

While in the Bush administration, Powell regularly clashed with neoconservatives, some of whom are now advising Romney. Powell said he has “trouble with” some of Romney’s “very strong neoconservative views.”

While Powell has endorsed the Democratic presidential candidate in back-to-back elections, he said he remains a Republican.

“I think I’m a Republican of more moderate mold and that’s something of a dying breed, I’m sorry to say,” Powell said. “But, you know, the Republicans I worked for are President Reagan, President Bush 41, the Howard Bakers of the world, people who were conservative, people who were willing to push their conservative views, but people who recognize that at the end of the day you got to find a basis for compromise. Compromise is how this country runs.”

Powell said he had a “very good conversation” with Romney a few weeks ago, and said he regularly speaks to Obama. Neither man directly asked Powell for an endorsement, and Powell said he didn’t alert either campaign before making his announcement Thursday.